Potential C4 owner
Thread Starter
Intermediate
Joined: Apr 2019
Posts: 31
Likes: 6
From: Edmonton, AB, Canada
Potential C4 owner
Hey C4 owners,
I am, hopefully, going to purchase my first Toy, looking at a 1994 Corvette, LT1, 6spd, 81,000km (50,000miles for the south of the border guys) in Brilliant Red Metallic on Friday.
Been reading up on old posts and what not on here and it seems to be the only major issue is the Optispark Distributor. Is there any way of knowing if it needs to be replaced?... or is it one of those things that when it goes, it goes...
Also, is there anything else I should be checking in particular? (Does not have FX3 suspension)
Appreciate any feedback you can give,
Thanks
I am, hopefully, going to purchase my first Toy, looking at a 1994 Corvette, LT1, 6spd, 81,000km (50,000miles for the south of the border guys) in Brilliant Red Metallic on Friday.
Been reading up on old posts and what not on here and it seems to be the only major issue is the Optispark Distributor. Is there any way of knowing if it needs to be replaced?... or is it one of those things that when it goes, it goes...
Also, is there anything else I should be checking in particular? (Does not have FX3 suspension)
Appreciate any feedback you can give,
Thanks
Racer
Joined: Feb 2018
Posts: 389
Likes: 77
Welcome to the forum 
As far as having a bad Opti a stumble off idle and a stumble/miss under high load/low rpm and a lack of power are some symptoms but depending on the condition of the REST of the ignition components those can also be symptoms changing the plugs wires coil and module FIRST if you’re having an issue there is code 16 “Low Resolution Pulse Failure" that can be also leaking water pumps are a very common issue on LT1’s changing BOTH at the same time if one or the other is giving you a problem is the way to go..
As far as having a bad Opti a stumble off idle and a stumble/miss under high load/low rpm and a lack of power are some symptoms but depending on the condition of the REST of the ignition components those can also be symptoms changing the plugs wires coil and module FIRST if you’re having an issue there is code 16 “Low Resolution Pulse Failure" that can be also leaking water pumps are a very common issue on LT1’s changing BOTH at the same time if one or the other is giving you a problem is the way to go..
Last edited by Y-bodluvr; Apr 9, 2019 at 11:20 AM.
Racer
Joined: Aug 2008
Posts: 388
Likes: 116
From: Jackson Michigan
Welcome CDN94C4,
I will echo what pacoW said. If you can do your own wrenching, it's not too difficult of a car to work on. The Optispark debate rages on here in the Forum, almost on a daily basis. The 94 has an non-vented Optispark, which most likely will cause issues at some time in the future. You can search the Forum, as there are a lot of posts on the vented vs non-vented Optispark. The venting is desired to remove the moisture and ozone that builds up in the cap. You can retrofit a vent into the 94 Opti. It's not terribly difficult. I did it on a 94 engine last year. Best of luck, and if you do buy it, be sure to post some pictures!
Regards,
John
I will echo what pacoW said. If you can do your own wrenching, it's not too difficult of a car to work on. The Optispark debate rages on here in the Forum, almost on a daily basis. The 94 has an non-vented Optispark, which most likely will cause issues at some time in the future. You can search the Forum, as there are a lot of posts on the vented vs non-vented Optispark. The venting is desired to remove the moisture and ozone that builds up in the cap. You can retrofit a vent into the 94 Opti. It's not terribly difficult. I did it on a 94 engine last year. Best of luck, and if you do buy it, be sure to post some pictures!
Regards,
John
Thread Starter
Intermediate
Joined: Apr 2019
Posts: 31
Likes: 6
From: Edmonton, AB, Canada
Thanks, car is in pretty incredible condition, original US car, No rust or corrosion, been in Canada since 2013.
I have only seen it in pictures however. Test driving it and seeing it in person will be the deciding factor of course.
I have only seen it in pictures however. Test driving it and seeing it in person will be the deciding factor of course.
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
Do not let the optispark boogeyman scare you away from a good LT1 car. Remember that failures are commonly discussed on forums but reliable parts discussions are more rare. The location of the optispark under the distributor is unfortunate but I've had two LT1 cars (vented) and both have been bulletproof reliable... many road trips and never skipped a beat, ever. Recommend converting to vented opti if you buy 1992-1994. Welcome to the forum 
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Thread Starter
Intermediate
Joined: Apr 2019
Posts: 31
Likes: 6
From: Edmonton, AB, Canada
Sounds good DGXR, I will look into venting the optispark.
With this optispark issue, should I completely avoid driving it in the rain? (I don't plan on driving it in the rain at all but we can't control mother nature)
With this optispark issue, should I completely avoid driving it in the rain? (I don't plan on driving it in the rain at all but we can't control mother nature)
Racer
Joined: Feb 2018
Posts: 389
Likes: 77
NO you shouldn’t avoid driving it in the rain driving it I woukdnt drive it in FLOODS though but that’s just common sense probably the two main ways the optis get wet and fail is from the leaking water pump and washing the engine..
Melting Slicks
Joined: May 2013
Posts: 2,692
Likes: 349
From: Sacramento California
The distributors are usually sealed pretty well so rain probably won't hurt it... although generally I would avoid downpours and deep puddles in a Corvette 
I don't drive mine in the rain simply because it breaks traction too easily and I don't like having to hold back all the time. Plus everyone else has less traction too, so all the distracted drivers have more potential for damage and injury. No thanks. I drive the pickup in wet weather.
I don't drive mine in the rain simply because it breaks traction too easily and I don't like having to hold back all the time. Plus everyone else has less traction too, so all the distracted drivers have more potential for damage and injury. No thanks. I drive the pickup in wet weather.
Thread Starter
Intermediate
Joined: Apr 2019
Posts: 31
Likes: 6
From: Edmonton, AB, Canada
Haha yeah driving this Corvette is going to be a learning curve, I have a slightly lifted Silverado VortecMax and she doesn't give a what about weather or road conditions.
Burning Brakes
Joined: Jan 2019
Posts: 1,225
Likes: 682
From: Park City, TN
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Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Welcome to the Forum and good luck with your C4 search/purchase.
Once you sit in and drive the car and check out all the options/features you will either be sold or move on the search.
Once you sit in and drive the car and check out all the options/features you will either be sold or move on the search.
Le Mans Master
Joined: Oct 2004
Posts: 7,706
Likes: 485
From: Everett WA
C4 of Year Finalist (appearance mods) 2019
Welcome to the C4 world. Everything looks to be nice and clean. That is a nice color combo! When you go to test the car, take your time and make sure that all the lights work properly and that all of the controls and buttons work as they should. Driving in the rain will not hurt the opti system. Pressure washing the engine may well indeed hurt electrical components so don't pressure wash. If you intend to keep the car and drive it, the 2-volume Factory Service Manual will probably come in handy.
Team Owner
Joined: Jul 2004
Posts: 28,432
Likes: 3,285
From: Hartford WI
While it all looks nice, it may not be on the inside. I would first off inform the seller you are getting a PROFESSIONAL mechanic to give it a Pre Delivery Inspection which will include scanning for all the codes and a compression test. If he balks, run like hell. "But I know cars. Why should I pay for it?". Well. see below.
1, You won't be sucked into buying something AND GLOSSING OVER PROBLEMS just because he infected you with the "Corvette Fever".
2. You won't be blamed for any breakage since the shop has insurance.
3. The guy will be neutral and have the tools and engine bay
1, You won't be sucked into buying something AND GLOSSING OVER PROBLEMS just because he infected you with the "Corvette Fever".
2. You won't be blamed for any breakage since the shop has insurance.
3. The guy will be neutral and have the tools and engine bay
Race Director
Joined: Oct 2012
Posts: 17,336
Likes: 6,509
From: Melbourne, FL
Looks like a nice car. With that few miles, the opti is probably fine. It wouldnt be a bad idea to replace the waterpump and gaskets as preventative, a water pump failure is the #1 cause of opti issues. The opti job isnt that bad... the heater core is, and I've done both.
Just be aware that this is the sort of an obsession. You will likely want to upgrade within the year.
Just be aware that this is the sort of an obsession. You will likely want to upgrade within the year.